A Novel Technique for Sterilization Using a Power Self-Regulated Single-Mode Microwave Cavity
Abstract
:1. Introduction
2. Materials, Methods, and Experimental Set Up
2.1. Materials
2.2. Software Implementation
2.3. Microbial Determinations and Food Substrates
3. Results and Discussion
3.1. Permittivity Characterization
3.2. Resonance
3.3. Temperature Profiles
3.4. Heat Inactivation of Bacillus cereus
- Higher loss factors lead to steeper temperature increase in the first heating stage, when a constant microwave power is applied to the cavity, since a higher loss factor yields a larger heat generation. Consequently, the target temperature is reached faster in the sample and, therefore, it is treated at the target temperature for a longer time. This rationale cannot be applied to the heating control stage, since there the power is controlled to keep the target temperature and, therefore, the heating generation is not directly related to the loss factor.
- Heat transfer by conduction inside the sample is higher with lower lipid content, since the thermal conductivity of the water, as a polar molecule, is higher than that of lipids, which are non-polar molecules.
- The presence of lipids can also have a protective effect on the spores of Bacillus cereus [25].
4. Conclusions
Acknowledgments
Author Contributions
Conflicts of Interest
References
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Process | Pressure | Time | Objective |
---|---|---|---|
Low temp. | No | 100 s | 60 °C |
High temp. | Yes | 50 s | 100 °C |
High temp. | Yes | 50 s | 110 °C |
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Reverte-Ors, J.D.; Pedreño-Molina, J.L.; Fernández, P.S.; Lozano-Guerrero, A.J.; Periago, P.M.; Díaz-Morcillo, A. A Novel Technique for Sterilization Using a Power Self-Regulated Single-Mode Microwave Cavity. Sensors 2017, 17, 1309. https://doi.org/10.3390/s17061309
Reverte-Ors JD, Pedreño-Molina JL, Fernández PS, Lozano-Guerrero AJ, Periago PM, Díaz-Morcillo A. A Novel Technique for Sterilization Using a Power Self-Regulated Single-Mode Microwave Cavity. Sensors. 2017; 17(6):1309. https://doi.org/10.3390/s17061309
Chicago/Turabian StyleReverte-Ors, Juan D., Juan L. Pedreño-Molina, Pablo S. Fernández, Antonio J. Lozano-Guerrero, Paula M. Periago, and Alejandro Díaz-Morcillo. 2017. "A Novel Technique for Sterilization Using a Power Self-Regulated Single-Mode Microwave Cavity" Sensors 17, no. 6: 1309. https://doi.org/10.3390/s17061309
APA StyleReverte-Ors, J. D., Pedreño-Molina, J. L., Fernández, P. S., Lozano-Guerrero, A. J., Periago, P. M., & Díaz-Morcillo, A. (2017). A Novel Technique for Sterilization Using a Power Self-Regulated Single-Mode Microwave Cavity. Sensors, 17(6), 1309. https://doi.org/10.3390/s17061309